What is the difference between fully insured and self insured health insurance plans?

The main difference between fully insured and self-insured health insurance plans is in how the financial risk is managed. In a fully insured plan, the employer pays a premium to an insurance company, which then assumes the financial risk for providing healthcare coverage. In a self-insured plan, the employer takes on the financial risk and pays for employees' healthcare costs directly, often with the help of a third-party administrator.